四分律行事鈔資持記 2.229

2.229

四明防非，初文。現在無非者，此約對治心行，以論三世。防是預擬，不令起非；對治現前，則防未非；纔失正念，即落過非；故知現在無有防義。

Fourth, explaining the prevention of wrongdoing; the first text. "In the present there is no wrongdoing": this discusses the three times in terms of the mental practice of the remedy. Guarding is anticipatory preparation so as not to allow wrongdoing to arise; when the remedy is present, it guards against future wrongdoing; the moment right mindfulness is lost, it falls into past wrongdoing; therefore one knows that in the present there is no meaning of guarding.